vmalloc.c: fix double error checking

There is no need for double error checking.
Signed-off-by: Figo.zhang <figo1802@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

@@ -168,11 +168,9 @@ static int vmap_page_range_noflush(unsigned long start, unsigned long end,
 		next = pgd_addr_end(addr, end);
 		err = vmap_pud_range(pgd, addr, next, prot, pages, &nr);
 		if (err)
-			break;
+			return err;
 	} while (pgd++, addr = next, addr != end);
 
-	if (unlikely(err))
-		return err;
 	return nr;
 }